Comparison Black&Decker ASI400 vs Ryobi R18I-0

The maximum pressure provided by the pump or compressor — in other words, the highest tyre pressure that can be achieved using this unit.

In most models, this figure is from 2.5 to 10 atm, and in mechanical pumps (manual and foot, see "Type") pressure of more than 10 atm is practically not found at all. This is due to the fact that even for heavy trucks, the optimal tyre pressure is usually about 5 – 9 atm (depending on a number of parameters — there are special formulas and tables for calculations); and in passenger car tyres, a pressure of more than 2.5 atm is extremely rarely used. However, there are compressors with higher pressure parameters — 11 – 15 atm, 16 – 20 atm and even higher. The meaning of such characteristics is mainly in the "power reserve": a higher working pressure contributes to faster pumping. However, be careful not to over-inflate the tyre and damage it.

The capacity of the compressor (see "Type") is the maximum amount of air that it can pump into the tyre in a minute.

Higher performance reduces the time required to inflate the wheel; on the other hand, this parameter directly affects the dimensions, weight, power consumption and price of the compressor. So it is worth choosing according to performance, taking into account real needs. So, for a “duty” tyre inflation in a passenger car, a compressor with a low operating speed is quite enough — up to 20 L / min inclusive. And if the speed of full pumping is also important for you (for example, after replacing the rubber) — you can choose a unit for 21 – 40 L / min. In turn, models with more solid characteristics — 41 – 60 L / min and more — are intended mainly for heavy equipment like SUVs, trucks, tractors, etc.

Separately, it should be noted that this parameter is NOT suitable for calculating the exact inflation time (even if the exact volume of air in the wheel is known). The fact is that the actual performance of the compressor is always lower than the claimed one: the figures in the characteristics are indicated for free air outlet, and when pumping the wheels, the pumping speed will inevitably be lower due to the resistance of the nipple.

Ways of connection to the power supply provided in the design of the compressor (see "Type").

— Cigarette lighter. Connection to a standard cigarette lighter socket (or a separate auto socket of the same format). This method is convenient because the compressor does not need to open the hood. On the other hand, cigarette lighters have limits on maximum power, and in different cars (and even in different sockets of the same car), these limits can vary markedly. See Power Consumption for details.

— Crocodiles. Connect directly to the battery terminals using crocodile clips. This method is somewhat more complicated than working from the cigarette lighter — you need to open the hood and pull the wires to the battery. On the other hand, it allows you to use the power of the on-board network to the fullest without worrying about overloads and the integrity of the fuses, making it suitable for even the most powerful and performant compressors. In addition, the “crocodiles” device can be connected not only to the on-board network, but also to a separate battery; in some cases, this possibility is useful (for example, if the car’s own battery is already running low, but there is a “fresh” battery nearby).

— Cigarette lighter / "crocodiles". The ability to use any of the connection options described above is optional. This provides convenience and al...lows you to choose the optimal format of work depending on the situation. For example, for quick pumping of one or two wheels, you can use the cigarette lighter, but for long-term work, food through the “crocodiles” is better suited.

— Fork. Plug for connecting to a regular 230 V socket (see "Power"). It is used in compressors having only this type of supply.

— Cigarette lighter / plug. Available on both 12V and 230 V models; for the first, a cigarette lighter is used, for the second, a plug.

— Cable (to the battery). Connection directly to the battery using cables with flat terminals, which are clamped into the battery terminals when connected. This design provides a tighter contact than the "crocodiles" described above, but is less convenient when connecting and disconnecting the compressor.

The length of the hose through which air is pumped into the tyre. The larger it is, the more convenient the device is to use. But it is rare that the compressor is left far from the wheel, especially if a pressure gauge is placed on the device, which must be periodically checked. For domestic use in cars, a one and a half metre long hose is enough. Powerful and performant models can be equipped with a hose of 7 metres or more, but these are more solutions for commercial use in car services.

The presence of the function of bleeding air in the design of the device.

This function is found exclusively in electric compressors (see "Type"). It, in fact, allows you to run the compressor "in the opposite direction" — not for pumping, but for drawing air. This mode can be useful if you need to quickly deflate a large inflatable object — for example, a mattress: manually blowing off often turns out to be a rather long and tedious task, and besides, it is not always possible to effectively remove residual air, while the compressor handles with this without problems.

Usually, for work with bleeding, a special hole is provided on the body, to which the air hose must be rearranged.

The presence of backlight pressure gauge in the design of the device.

This function requires a power supply, so it is found mainly in the corresponding type of device — compressors (see "Type"). Its purpose is generally obvious: thanks to the backlight, you can easily see the readings of the pressure gauge in low light conditions and even in complete darkness. Such an opportunity when working with a compressor is useful — and not only at dusk and at night, but even in the daytime: many garages, boxes and other places where you have to service a car are very sparingly lit, and even during the day the pressure gauge scale may not be visible without additional illumination.

Many pumps/compressors come in special cases or cases that make them easy to store and transport. Under the cover, usually, we mean a classic cloth bag, which pumps are often equipped with and which rather protects them from dirt, dust, etc. But compressors are often supplied in plastic cases, they are convenient, inexpensive, rust-resistant and equipped with a convenient carrying handle . Plastic is considered less durable, but it is quite enough to provide the necessary protection.